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2

Functional Description

The VHC153 is a dual 4-input multiplexer. It can select two

bits of data from up to four sources under the control of the

can be used to strobe the outputs independently. When the

tion of a 2-pole, 4-position switch, where the position of the

switch is determined by the logic levels supplied to the

Select inputs. The logic equations for the outputs are

shown below.

Truth Table

H

= HIGH Voltage Level

L

= LOW Voltage Level

X

= Immaterial

Logic Diagram

Please note that this diagram is provided only for the understanding of logic operations and should not be used to estimate propagation delays.

Select

Inputs (a or b)

Output

Inputs

E

Z

X

X

H

X

XXX

L

LL

LL

X

X

X

L

L

L

L

H

XXX

H

HL

L

X

L

X

X

L

HL

L

X

H

X

X

H

LH

L

X

X

L

X

L

LH

L

X

X

H

X

H

HH

L

X

X

X

L

L

HH

L

X

X

X

H

H